AIR (Allow Independent Road-testing) welcomes the publication of the CEN workshop agreement CWA 17379 general guidelines on the real-drive methodology for compiling comparable emissions data for NOx in urban driving.

Issued by the European Committee for Standardisation (CEN), the CEN Workshop Agreement (CWA 17379 produced by CEN Workshop 90) provides, for the first time, a testing methodology to conduct on-road tests to capture emissions data, from different test centers, in such a way the data collected will enable the fair comparison of the emissions performance of vehicles. Its applicability to vehicles of a wide range means that it forms a valuable complement to the new Real Driving Emissions (RDE) regulation.

Publication of the guidelines is the result of dialog between more than 40 scientists, consumer groups, policymakers, engineers and NGOs, working together under the chairmanship of Nick Molden, founder of Emissions Analytics and co-founder of AIR, to develop this standardized and recognized methodology.

The workshop reached consensus on the specific and detailed criteria which must be followed during the tests to ensure that a result is valid and repeatable across multiple instances of the same vehicle captured using Portable Emissions Measurement Systems (PEMS) equipment.

The stringent requirements of the methodology demand the testing of at least two matching examples of each model, during three separate journeys, including at least five, 10km (6.2mph) trips conducted on paved roads, at an average speed between 20km/h (12.4mph) and 40km/h (24/8mph).

Massimo Fedeli, co-founder and operations director of AIR, said, “This a landmark day for independent testing of vehicle emissions. The CEN Workshop Agreement 17379 reflects more than a year of collaboration to reach alignment on methodology for reporting the actual NOx emissions from vehicles in urban driving, so that consumers can buy the cleanest car, based on scientific fact. only when armed with such information can policymakers in cities and governments create fair and effective rules to tackle urban air quality problems.”